This invention relates to jigs and fixtures, and particularly to a novel modular method and system for setting fixed-angles by revolving triads of interlocking holes of a modular tooling system.
An unrestricted workpiece has six degrees of freedom with respect to the axes of a coordinate system: three along-axis-moving degrees and three around-axis-revolving degrees as schematically shown in see FIG. 13. For the workpiece to be machined, the relative degrees of freedom must be restricted by a jig or fixture as shown for example, in FIG. 14. So, evidently, if any workpiece is to be fixed in a modular tooling system, the interlocking features of the system must be albe to freely move along and revolve around the axes for the features to be adjusted where they are necessary for constructing fixture bodies and fixing locators or clamps. In other words, a good modular tooling system should have two kinds of adjustability, along and around the coordinate axes. Since the advantage of slots is that they offer adjustability along axes, and holes provide adjustment around axes, the available hole type modular tooling system must be improved to offer the full adjustability by:
1. introducing slots into the hole type system to solve the problem of adjustability along axes and, PA0 2. bringing the advantage of adjustability around hole axes into full play.
The solution of adjustability around the axes is covered by this patent application, and adjustability along the axes is covered in a separate pending patent application.
Since the above-mentioned principles for modularizing of jigs and fixtures are proposed by the inventors after their thorough study of the available modular tooling technology, this invention is based on also such principles.
There have been many styles of fixed-angle constructions in the scope of available jigs and fixtures, but generally speaking these constructions may be divided into three types: stable, adjustable, and modular, and the adjustable unit may further be divided into the direct adjustor and the comparator adjustor. The stable or non-re-adjustable type is a kind of unreadjustable constructions fabricated specially for a certain workpiece and operation. The adjustable type is a kind of units adjustable to the change of workpieces and operations. The modular construction is what is assembled with premanufactured modules from a modular angling system, and is dismountable for subsequent assemblies after use. The direct adjustor is a unit adjustable to a certain angle without rigging and indicating, and the comparator-adjust or type must be operative by rigging and indicating. U.S. Pat. Nos. 165,840, 3,736,666 and 341,020 are of the direct adjustor type, while the present invention is of the modular angling type. The stable construction can provide a more compact and more rigid structure than the adjustable construction, but can not offer angular adjustability and modularity. The comparator-adjustable unit can provide stepless angles and a compact construction over the direct adjustor, but can not be set up precisely and fast because of the necessity of rigging and indicating, and can not offer rigidity and stability because they hold a workpiece only by friction. A complete modular angling system should comprise a set of angular modules which can selectively be assembled into various constructions of different angles without readjustability, that is, the modular angling system may be a complete system which can offer advantages of the adjustable unit, and the assembled modular construction may be the same as the stable or non-adjustable construction is. However, of the available hole type modular tooling systems there has been no one which can provide the modular style of angular constructions, and of the available slot type modular tooling systems there have been only one or two systems which have been using fixed-angle setting pads or supports in some common angles that do not essentially have angular modularity; in all the available systems including hole and slot types, what has been in common use is the adjustable angular unit, that is, almost none of the available systems has related to the modular anglig system.